The prior art is documented with examples of patient monitory devices. A first example of these is the patient monitoring apparatus of EP 0 107 058 which includes a switching device and a monitoring device. The switching device includes a flexible base member having an aperture therethrough and sandwiched between two conductive members and covered with two cover members. When a patient lies on the switching device, the base member is deformed allowing the conductive members to close the circuit. The monitoring device includes a binary signal generator, a time delay which produces a signal when the signal generator has been operated for a predetermined time, a latching device, and an alarm signal generator and alarm control device for varying the nature of the alarm signal produced by the generator.
U.S. Pat. No. 9,253,891, to Williams, teaches a sensor pad that is adapted to be positioned on a patient's bed or chair as part of a monitoring system that provides a signal to a caregiver when the patient rises from the bed or chair and which also indicates when the pad is near failure. The sensor pad includes specialized contact plate patterning that creates zones on the sensor pad.
U.S. Pat. No. 7,666,151, to Sullivan et al., teaches a variety of devices, systems and methods for providing patient monitoring of such parameters as body motion, body position, respiratory rate and/or heart rate. A further version of a wireless patient monitoring system is depicted in U.S. Pat. No. 8,416,084, to Belmann et al., which teaches a variety of room based sensors disposed within room units and which relay collected data to a central controller.